Conventionally, a corneal reflex method of detecting a gaze by using an infrared (IR) ray is generally known as a method of performing gaze detection. In the corneal reflex method, an infrared ray is emitted and an image of an eye part of a user is photographed, and a gaze direction is detected from a positional relationship between a position of the infrared ray on the image acquired by the photographing, that is, a bright spot of the infrared ray and a pupil of a user to be detected.
Incidentally, in a case where gaze detection is performed in an environment with outside light, since sunlight as outside light includes an infrared component, there is a case where the outside light becomes a disturbance and influences the gaze detection.
Thus, in order to reduce an influence of a disturbance, a method of removing a disturbance component from an image photographed by emission of an infrared ray by using an image photographed in a state in which an infrared ray is not emitted has been proposed (see, for example, Patent Document 1).